The Regular-Expressions.info website has a new quick reference to regular expressions that lists all of the regex syntax in one single table along with a link to the tutorial section that explains the syntax. The quick reference is ordered by syntax whereas the full reference tables are ordered by feature. There are multiple entries for some of the syntax as different regex flavors may use the same syntax for different features.

Use the quick reference if you’ve seen some syntax in somebody else’s regex and you have no idea what feature that syntax is for. Use the full reference tables if you already know the feature you want but forgot which syntax to use.

Of course, an even quicker reference is to paste your regex into RegexBuddy, select the application you’re working with, and click on the part of the regex you don’t understand. RegexBuddy then selects the corresponding node in its regex tree which summarizes exactly what the syntax you clicked on does in your regex. If you need more information, press F1 or click the Explain Token button to open the relevant page in the regex tutorial in RegexBuddy’s help file.